What’s the point of determining which is more important if not to define some sort of regulation around smoking?

The point is to discuss the matter merely as an intellectual exercise. Not every reflection on the merits of human behaviors is a precursor to legislation. There are plenty of discussions about rude or bothersome behaviors that do not involve criminalizing them. Would all these discussions only be worthwhile if they lead to "some sort of regulation"? If we wanted to discuss which right is more important — the right to blast music on the train or the right for other passengers to maintain the status quo (i.e. no music) — would you dismiss that conversation unless they were talking about creating legislation to control that problem? As an aside, it is interesting to note that in some places that actually is a misdemeanor, so state control over nuisances like this do exist.

See my above comment, I added an example. I’ll include it here just for the sake of it: alcohol.

This entire example is a false equivalence. The common factor should not just be unhealthful behaviors (i.e. both alcohol and cigarettes are simply unhealthful), but behaviors that are unhealthful to those who did not choose to engage in that unhealthful behavior. Otherwise, there is not one behavior being evaluated against another (a person having the right to drink vs. the people around him/her having the right to ____?). In other words, the problem here is that cigarette smoking can be unhealthful or a nuisance to those around the smoker. Alcohol in your example is only unhealthy to the drinker. The more relavent question to your example would be whether or not smoking and drinking alcohol should be accepted considering that they are unhealthy to those engaging in those activities. In fact, the more proper equivalence — alcohol being a nuisance to those around the drinker — is often regulated; i.e. in the form of laws against public intoxication. However, this is still not a direct equivalence because the question is about behaviors that are unhealthful to second parties but still accepted, and public intoxication is not "unhealthful but accepted" in this regard.

Preferring something means you want it to be.

You can prefer things, really want them to be, and realize it is not feasible to have that happen. That is the concept of idealism in a nutshell. It’s kinda mind-numbing that I even have to break this down.